Process for manufacture of an allyl ether

ABSTRACT

A process for production of an allyl and/or methallyl ether of a tri or polyhydric alcohol is disclosed. Said process comprises (i) subjected at least one cyclic formal of a tri or polyhydric alcohol to allylation, (ii) subjecting obtained allyl and/or methallyl ether of said cyclic formal to reaction with at least one alcohol and optionally an intermediate and/or a final purification step. In further aspects the present invention refers to an allyl and/or methallyl ether yielded in said process.

The present invention relates to the production of an allyl and/ormethallyl ether of a tri or polyhydric alcohol, such as a2-alkyl-2-hydroxyalkyl-1,3-propanediol or a2,2-dihydroxyalkyl-1,3-propanediol and/or a cyclic formal thereof. Morespecifically, the invention relates to a novel process for thepreparation of an allyl and/or methallyl ether from a waste streamcomprising at least one cyclic formal of a said tri or polyhydricalcohol. In further aspects the present invention refers to an allyland/or methallyl ether yielded in said process.

Allyl and methallyl ethers of polyhydric alcohols are typically producedaccording to the Williamson synthesis by reacting a polyhydric alcoholwith at least one allyl or methallyl halide, such as allyl bromide ormethallyl chloride, in the presence of a basic catalyst.

Tri and polyalcohols having for instance a neopentyl structure, such astrimethylolpropane, trimethylolethane and pentaerythritol are normallysynthesised in an alkali catalysed aldolcondensation of formaldehyde anda second aldehyde. Yielded aldolaldehyde is subsequently reduced tocorresponding alcohol, by means of a so called Cannizzaro reaction, witha further amount of formaldehyde in the presence of a strong base. Thereaction can alternatively be carried out by means of catalytichydration. The synthesis as well as recovery of obtained reactionproduct normally yield secondary products, such as formals (formaldehydeacetals). The syntheses yield linear and cyclic formals, such as1,3-dioxolanes and 1,3-dioxanes. Linear formals are when exposed toacidic treatment, for instance when passing an ion exchanger, duringrecovery of the primary product transformed into cyclic formals.

Cyclic formals are also yielded during recovery if a synthesised tri orpolyalcohol under acidic conditions is in contact with formaldehyde.This occurs for instance during an evaporation procedure, wherein waterand excess of formaldehyde are evaporated. Formation of formals occurswhen a 1,3-diol structure in a di, tri or polyalcohol reacts with forinstance formaldehyde to corresponding 1,3-dioxane. Glycerol cansimilarly yield formals, such as 4-hydroxymethyl-1,3-dioxolane and5-hydroxy-1,3-dioxane. Cyclic formals are furthermore yielded duringother polyalcohol syntheses, such as acid catalysed etherification, asdisclosed in for instance the U.S. Pat. No. 3,673,226.

Formals yielded as by-products in a synthesis of a polyhydric alcoholare continuously subjected to development efforts making said formalstechnically and commercially valuable. One such achievement isrepresented by 5-ethyl-5-hydroxymethyl-1,3-dioxane (cyclictrimethylolpropane formal) now frequently used for instance as flowadditive in cement compositions and for preparation of reactive acrylicdiluents.

The present invention quite unexpectedly provides a process whereincyclic formals, for instance yielded as by-products in a synthesis of atri or polyhydric alcohol, are converted to technically and commerciallyvaluable products, such as allyl ethers of tri and polyhydric alcoholsor allyl ethers of said cyclic formals. The present inventionaccordingly refers to a process for production of an allyl and/ormethallyl ether of a tri or polyhydric alcohol.

The process of the present invention comprises the steps of

-   i) subjecting at least one cyclic formal of a tri or polyhydric    alcohol to allylation by reaction with at least one allyl and/or    methallyl halide in the presence of a catalytically effective amount    of at least one basic catalyst, whereby a reaction mnixture    comprising at least one allyl and/or methallyl ether of said cyclic    formal is yielded, and-   ii) subjecting in step (i) obtained allyl and/or methallyl ether of    said cyclic formal to reaction with at least one alcohol, having one    or more hydroxyl groups, optionally in presence of a catalytically    effective amount of at least one organic acid catalyst, whereby a    reaction mixture comprising at least one allyl and/or methallyl    ether of said tri or polyalcohol and at least one formal of said    alcohol,    and optionally an intermediate purification step wherein the    reaction mixture obtained in step (i) is purified prior to    initiation of step (ii) and/or a final purification step wherein the    reaction mixture obtained in step (ii) is purified.

Step (i) of said process is preferably performed at atmospheric or at areduced or increased pressure and at a temperature of 60-140° C. andstep (ii) is likewise preferably performed at a reduced pressure, suchas a pressure of less than 15 m=Hg, or at a atmospheric or increasedpressure and at a temperature of 80-160° C. Said allyl and/or methallylhalide and said basic catalyst are in step (i) advantageously addedcontinuously to the reactor.

Said optional intermediate purification step comprises, in preferredembodiments of the process of the present invention, at least oneextraction, such as mixing the reaction mixture obtained in step (i)with water and allowing obtained mixture to separate in a water phaseand an organic phase and recovery of said organic phase. Said optionalintermediate purification can also and optionally comprise furtherpurifying, of for instance said organic phase, by for instanceevaporation, such as distillation, at a pressure of for instance lessthan 15 mm Hg.

Said optional final purification step comprises, in preferredembodiments of the process of the present invention, purification of thereaction mixture obtained in step (ii) by for instance evaporation, suchas distillation, at a pressure of for instance less than 15 mm Hg. Saidoptional final purification may also comprise extraction as for instancedisclosed above for said optional intermediate purification.

The cyclic formal subjected to allylation is suitably a recovered andoptionally purified by-product or is present in a mixture, such as awaste stream which optionally is purified, of by-products from a plantwherein a tri or polyalcohol, such as glycerol, trimethylolethane,trimethylolpropane or pentaerythritol, is synthesised and produced.

Preferred embodiments of said cyclic formal include cyclic formalshaving a 1,3-dioxolane and most preferably a 1,3-dioxane structure, suchas cyclic formals of 1,2,3-propanetriols,2-alkyl-2-hydroxyalkyl-1,3-propanediols,2-alkyl-2-hydroxyalkoxy-1,3-propandiols,2-alkyl-2-hydroxyalkoxyalkyl-1,3-propanediols,2,2-dihydroxyalkyl-1,3-propanediols,2,2-di-hydroxyalkoxy-1,3-propanediols,2,2-dihydroxyalkoxyalkyl-1,3-propanediols and dimers, trimers andpolymers thereof. Said cyclic formal can suitably be exemplified by acyclic formal of glycerol, trimethylolethane, trimethylolpropane,diglycerol, ditrimethylolethane, ditrimethylolpropane, pentaerythritol,dipentaerythritol and ethoxylated and/or propoxylated species thereof.Preferred embodiments of said cyclic formal include4-hydroxyalkyl-1,3-dioxolanes, 5-hydroxy-1,3-dioxanes,5-alkyl-5-hydroxy-1,3-dioxanes, 5-alkyl-5-hydroxyalkyl-1,3-dioxanesand/or 5,5-hydroxyalkyl-1,3-dioxanes. The most preferred cyclic formalsare cyclic formals of tri or polyhydric alcohols having a neopentylstructure, such 2,2-substituted 1,3-propanediols. Especially preferredembodiments of the present invention include subjecting for instance4-hydroxyalkyl-1,3-dioxolane, 5-hydroxy-1,3-dioxane,5-alkyl-5-hydroxy-1,3-dioxane, 5-alkyl-5-hydroxyalkyl-1,3-dioxane and5,5-hydroxyalkyl-1,3-dioxane to allylation in step (i) and subjectingobtained allyl and/or methallyl ether to reaction in step (ii).

Said at least one allyl and/or methallyl halide is, in embodiments ofthe present invention, preferably allyl and/or methallyl bromide and/orchloride and said at least one basic catalyst is suitably and preferablyat least one alkali and/or alkaline earth metal hydroxide, alkoxideand/or carbonate, such as potassium and/or sodium hydroxide, carbonateand/or methoxide.

Said at least one alcohol, having one or more hydroxyl groups, in step(ii) subjected to reaction with the product obtained in step (i) is mostpreferably at least one mono, di, tri or polyalcohol, such as at leastone alkanol, alkanediol, 2,2-alkyl-1,3-propanediol,2-alkyl-2-hydroxyalkyl-1,3-propanediol,2,2-dihydroxyalkyl-1,3-propanediol or at least one dimer, trimer orpolymer of a said alcohol. Embodiments of said preferred alcoholsinclude the most preferred species, which include methanol,2-ethylhexanediol, ethylene glycol, neopentyl glycol, trimethylolpropaneand trimethylolethane.

Said at least one optional organic acid catalyst is most preferablyp-toluenesulphonic acid and/or methanesulphonic acid.

The most preferred embodiments of the process of the present inventioninclude embodiments wherein said cyclic formal subjected to allylationin step (i) is 5,5-dihydroxymethyl-1,3-dioxane optionally present in amixture, such as a said waste stream, of by-products as disclosed aboveand that said alcohol in step (ii) subjected to reaction with in step(i) yielded allyl and/or methallyl ether is methanol ortrimethylolpropane.

In a further aspect the present invention refers to an allyl and/ormethallyl ether of a tri or polyhydric alcohol, which allyl and/ormethallyl ether is obtained by the process disclosed above. Said allyland/or methallyl ether is in the most preferred embodiments a monoallyl,diallyl, monomethallyl and/or dimethallyl ether of pentaerythritol andmost preferably obtained from 5,5-dihydroxymethyl-1,3-dioxane recoveredfrom or present in a mixture of by-products, such as a waste stream,yielded in a pentaerythritol synthesis.

In yet a further aspect the present invention refers to a novel allyland/or methallyl ether yielded in step (i) of the process according tothe present invention. Said allyl and/or methallyl ether is mostpreferably a monoallyl, diallyl, monomethallyl and/or dimethallyl etherof 5,5-dihydroxymethyl-1,3-dioxane, which dioxane is yielded asby-product in a pentaerythritol synthesis.

Without further elaboration, it is believed that one skilled in the artcan, using the preceding description, utilise the present invention toits fullest extent. The following preferred specific embodiments are,therefore, to be construed as merely illustrative and not limitative ofthe remainder of the disclosure in any way whatsoever. In the followingExamples 1-4 show embodiments of step (i) of the present process,Examples 5 and 6 show embodiments of step (ii) of the present process,Example 7 shown an embodiment of the optional intermediate purificationstep and Example 8 shows an embodiment of the optional finalpurification step.

EXAMPLE 1

A mixture of polyhydric compounds (Polyol PX™, Perstorp SpecialtyChemicals AB, Sweden) obtained from a pentaerythritol synthesis was inan amount comprising 853 g (4 moles) of the cyclic pentaerythritolformal 5,5-hydroxymethyl-1,3-dioxane subjected to reaction with 309 g (4moles) of allyl chloride in the presence of 352 g (4.4 moles) of sodiumhydroxide. The reaction was performed in a 2000 ml 3-necked reactionflask equipped with a thermometer, condenser, Dean-Stark receiver,stirrer and a drop funnel. The reaction was under stirring carried outat a temperature of 120° C. The reaction time was 7 hours. Yieldedreaction water was continuously collected in the Dean-Stark receiver.Obtained reaction mixture was neutralised with hydrochloric acid to a pHof 7. Volatile by-products were removed by evaporation at 60° C. and 10mm Hg and formed sodium chloride was removed by filtration.

877 g of the reaction mixture was recovered and GC analyses showed thata 61% selectivity of monallyl ether of cyclic pentaerythritol formal wasobtained with a 56% conversion of cyclic pentaerythritol formal.

EXAMPLE 2

Example 1 was repeated with the difference that Polyol PX™ in an amountcomprising 326 g (1.53 mole) of CPF was subjected to reaction with 296 g(3.83 moles) of allyl chloride and 337 g (4.21 moles) of sodiumhydroxide.

390 g of the reaction mixture was recovered and GC analyses showed thata 50% selectivity of monallyl ether of cyclic pentaerythritol formal wasobtained with a 100% conversion of cyclic pentaerythritol formal.

EXAMPLE 3

Example 1 was repeated with the difference that Polyol PX™ in an amountcomprising 759 g (4.97 moles) of CPF was subjected to reaction with 384g (4.97 moles) of allyl chloride and 437 g (5.46 moles) of sodiumhydroxide.

895 g of the reaction mixture was recovered and GC analyses showed thata 82% selectivity of monallyl ether of cyclic pentaerythritol formal wasobtained with a 72% conversion of cyclic pentaerythritol formal.

EXAMPLE 4

Example 1 was repeated with the difference that Polyol PX™ in an amountcomprising 1128 g (7.4 moles) of CPF was subjected to reaction with 687g (8.88 moles) of allyl chloride and 710 g (8.88 moles) of sodiumhydroxide.

1426 g of the reaction mixture was recovered and GC analyses showed thata 87% selectivity of monallyl ether of cyclic pentaerythritol formal wasobtained with a 88% conversion of cyclic pentaerythritol formal.

EXAMPLE 5

400 g of a reaction mixture, comprising 1.32 mole of monoallyl ether ofcyclic pentaerythritol formal, obtained in accordance with Examples 1-4,was subjected to reaction with 385 g (2.81 moles) of trimethylolpropanein the presence of 4.9 g (0.05 mole) of p-toluenesulphonic acid. Thereaction was performed in a 2000 ml 3-necked reaction flask equippedwith a thermometer, stirrer and a distillation column with a Sulzerpacking. The reaction was under stirring carried out at a temperature of135° C. and a pressure of 1 mm Hg. The reaction time was 6 hours.

1219 g of reaction mixture was recovered and GC analyses showed that a95% selectivity of pentaerythritol monoallyl ether was obtained with a87% conversion of monoallyl ether of cyclic pentaerythritol formal.

EXAMPLE 6

1500 g of a reaction mixture, comprising 7.91 moles of monoallyl etherof cyclic pentaerythritol formal, obtained in accordance with Examples1-4, was subjected to reaction with 2105 g (65.7 moles) of methanol inthe presence of 15.0 g (0.079 mole) of p-toluenesulphonic acid. Thereaction was performed in a 3-necked reaction flask equipped with athermometer, stirrer and a distillation column with a Sulzer packingwas. The reaction was under stirring carried out at a temperature of 85°C. and a pressure of 760 mm Hg. The reaction time was 72 hours.

EXAMPLE 7

1893 g of a reaction admixture, obtained in accordance with Examples1-4, comprising 93.3% monoallyl ether and 5.3% diallyl ether of cyclicpentaerythritol formal was purified in a batch distillation equipment ata pressure of 1 mm Hg. The distillation column was packed with a SulzerBX packing. The reflux was 10:1 at the beginning of the distillation and5:1 at the end.

1298 g of the main fraction was recovered. The distillation yield was73% and GC analyses showed a 99% purity of monoallyl ether of cyclicpentaerythritol formal.

EXAMPLE 8

1398 g of a reaction admixture, obtained in accordance with Examples 5and 6, comprising 89.9% pentaerythritol monoallyl ether was purified ina batch distillation equipment at a pressure of 1 mm Hg. The column waspacked with a Sulzer BX packing. The reflux was 10:1.

1113 g of the main fraction was recovered. The distillation yield was87% and GC analyses showed 98% purity of pentaerythritol monoallylether.

1. A process for production of an allyl and/or methallyl ether of a trior polyhydric alcohol wherein said process comprises the steps of: i)subjecting at least one cyclic formal of at least one tri or polyhydricalcohol to allylation by reaction with at least one allyl and/ormethallyl halide in presence of a catalytically effective amount of atleast one basic catalyst, whereby a reaction mixture, comprising atleast one allyl and/or methallyl ether of said cyclic formal, isyielded, and ii) subjecting in step (i) yielded allyl and/or methallylether of said cyclic formal to reaction with at least one alcohol,having one or more hydroxyl groups, optionally in presence of acatalytically effective amount of at least one organic acid catalyst,whereby a reaction mixture, comprising at least one allyl and/ormethallyl ether of said tri or polyhydric alcohol and at least oneformal of said alcohol, is yielded.
 2. A process according to claim 1,wherein said step (i) is performed at a temperature of 60-140° C.
 3. Aprocess according to claim 1, wherein said step (ii) is performed at atemperature of 80-160° C.
 4. A process according to claim 1, whereinsaid optional intermediate purification comprises extraction andoptionally further purification by evaporation.
 5. A process accordingto claim 1, wherein said optional final purification step comprisespurification of the reaction mixture obtained in step (ii) byevaporation.
 6. A process according to claim 1, wherein said at leastone cyclic formal is a recovered by-product or is present in a mixtureof by-products from a synthesis of a tri or polyalcohol.
 7. A processaccording to claim 1, wherein said at least one cyclic formal isrecovered from a waste stream and/or a mixture of by-products from asynthesis of a tri or polyalcohol and optionally that said cyclic formalis purified.
 8. A process according to claim 1, wherein said at leastone cyclic formal is at least one cyclic formal selected from the groupconsisting of a 1,2,3-propanetriol,2-alkyl-2-hydroxyalkyl-1,3-propanediol,2-alkyl-2-hydroxyalkoxy-1,3-propandiol,2-alkyl-2-hydroxyalkoxyalkyl-1,3-propanediol,2,2-dihydroxyalkyl-1,3-propanediol, 2,2-dihydroxyalkoxy-1,3-propanediolor 2,2-dihydroxyalkoxyalkyl-1,3-propanediol.
 9. A process according toclaim 1, wherein said at least one cyclic formal is at least one cyclicformal of at least one dimer, trimer or polymer selected from the groupconsisting of a 1,2,3-propanetriol,2-alkyl-2-hydroxyalkyl-1,3-propanediol,2-alkyl-2-hydroxyalkoxy-1,3-propandiol,2-alkyl-2-hydroxyalkoxyalkyl-1,3-propanediol,2,2-dihydroxyalkyl-1,3-propanediol, 2,2-dihydroxyalkoxy-1,3-propanediolor 2,2-dihydroxyalkoxyalkyl-1,3-propanediol.
 10. A process according toclaim 1, wherein said at least one cyclic formal is at least one cyclicformal selected from the group consisting of glycerol,trimethylolethane, trimethylolpropane, diglycerol, ditrimethylolethane,ditrimethylolpropane, pentaerythritol or dipentaerythritol.
 11. Aprocess according to claim 1, wherein said at least one cyclic formal isat least one cyclic formal selected from the group consisting of anethoxylated and/or propoxylated glycerol, trimethylolethane,trimethlolpropane, diglycerol, ditrimethylolethane,ditrimethylolpropane, pentaerythritol or dipentaerythritol.
 12. Aprocess according to claim 1, wherein said at least one cyclic formal isselected from the group consisting of at least one4-hydroxyalkyl-1,3-dioxolane, 5-hydroxy-1,3-dioxane,5-alkyl-5-hydroxy-1,3-dioxane, 5-alkyl-5-hydroxyalkyl-1,3-dioxane or5,5-hydroxy-alkyl-1,3-dioxane.
 13. A process according to claim 12,wherein at least one cyclic formal is selected from the group consistingof 5-hydroxy-1,3-dioxane, 5-methyl-5-hydroxymethyl-1,3-dioxane,5-ethyl-5-hydroxymethyl-1,3-dioxane or 5,5-dihydroxymethyl-1,3-dioxane.14. A process according to claim 1, wherein said at least one allylhalide is allyl, methallyl bromide or chloride.
 15. A process accordingto claim 1, wherein said at least one basic catalyst is at least onealkali or alkaline earth metal hydroxide, alkoxide or carbonate.
 16. Aprocess according to claim 15, wherein said at least one basic catalystis potassium or sodium hydroxide, carbonate or methoxide.
 17. A processaccording to claim 1, wherein said at least one alcohol, having one ormore hydroxyl groups, is at least one mono, di, tri or polyalcohol. 18.A process according to claim 17, wherein said at least one mono, di, trior polyalcohol is an alkanol, an alkanediol, a2,2-alkyl-1,3-propanediol, a 2-alkyl-2-hydroxyallkyl-1,3-propanediol, a2,2-dihydroxyalkyl-1,3-propanediol or a dimer, trimer, or polymer of asaid alcohol.
 19. A process according to claim 17, wherein said at leastone mono, di, tri or polyalcohol is methanol, 2-ethylhexanediol,ethylene glycol, neopentyl glycol, trimethylolpropane and/ortrimethylolethane.
 20. A process according to claim 1, wherein said atleast one organic acid catalyst is p-toluenesulphonic acid ormethanesulphonic acid.
 21. A process according to claim 1, wherein saidat leaset one cyclic formal subjected to allylation in step (i) is5,5-dihydroxymethyl-1,3-dioxane or a mixture, such as a waste stream,comprising 5,5-dihydroxymethyl-1,3-dioxane and that said alcohol, whichin step (ii) is subjected to reaction within step (i) yielded allyland/or methallyl ether, is trimethylolpropane.
 22. An allyl ether of atri or polyhydric alcohol, wherein it is yielded in the process ofclaim
 1. 23. An allyl and/or methallyl ether according to claim 22,wherein said allyl and/or methallyl ether is at least one monoallyl,dially, monomethallyl and/or dimethallyl ether of pentaerythritol.
 24. Anovel allyl and/or methallyl ether, wherein it is yielded in step (i) ofthe process according to claim
 1. 25. A novel allyl and/or methallylether according to claim 24, wherein said allyl and/or methallyl etheris at least one monoallyl, diallyl, monomethallyl and/or dimethallylether of 5,5-dihydroxymethyl-1,3-dioxane.
 26. A novel allyl and/ormethallyl ether according to claim 25, wherein said5,5-dihydroxymethyl-1,3-dioxane is yielded as by-product in a synthesisof pentaerythritol.
 27. A process according to claim 1, wherein said atleast one methallyl halide is allyl, methallyl bromide or chloride. 28.An methallyl ether of a tri or polyhydric alcohol, wherein it is yieldedin the process of claim
 1. 29. The process according to claim 4, whereinsaid purification step is distillation.
 30. The process according toclaim 5, wherein said purification step is distillation.